Rope



E. V. WYATT July 26, 1932.

ROPE

Filed March 5, 1930 Patented July 26, 1932 ERNEST V. WYATT, OFSOMERVILLE, MASSACHUSETTS norm Application filed March 5, 1930. SerialNo. 433,279.

. ropes and cordage as known to the seafaring profession, whichweaknesses have been recognlzed for many years but which, lnsofar as Iam advised, have neverbeen successfully over-' come. For example, theordinary fourstrand manila rope as used in purchases, boatfalls andvarious tackles aboard ship frequently is laid up into rope at therope-walk with a heart or core of hemp or other fibrous yarns twistedinto a strand. This strand hereinafter referred to as the core is necessary because without it the outside spirally laid up strands would formsharp apexes in the center of the rope, and soon internal friction wouldwear out these sharply bent fibers, thus shortening the life ofthe-rope. With the hemp coreinternal friction is not entirely eliminatedas the fibers composing the core rub against the fibers composing theouter strands.

'A weakness inherent in fiber core rope is apparent when a manila ropefor instance is subjected to sudden strain as in the case of hoisting orlowering a lifeboat in a seaway. The strain on the rope will cause it tostretch considerably, due partly to the elasticity of the fiber, andalso largely to the spirally twisted construction of the principalstrands of the rope as laid around the core.

The core of the rope located centrally throughout the entire length ofthe rope will be and in fact actually is, subjected to a direct strainwhich is far greater than the strain taken up by the four outer spirallylaid up strands. Frequently the corestrand is a smallerand weakerstrand. This being so, the core strand which is necessarily in thedirect line of forcewill part under severe strain, causing the structureof the rope at the loca-- tion. of the break to collapse. I

To overcome these difiiculties, I have provided the improved rope of myinvention with a core of rubber, rubber compound, or other elasticmaterial. This is adapted 'not only to overcome the weaknesses abovereferred to,

T but also increases the elasticity and life of the rope by cushioningand protecting the fibers.

strain is removed, the rubber expands and the The main spirally laidstrands of the rope are In contact with the rubber core and chafingbetween the strands and the core is practically eliminated. Under severestrain the rubber core will stretch and be compressed to some extent bythe strands.

To appreciate the rubber cushioning effect of my improved core, it isnecessary to understand that there are occasions at sea and perhapselsewhere that a rope such as I have reference to may be required topossess additional elastic qualities. For instance, when a heavy fibroustowing hawseror heavy rope laid anchor cable is subjected to its maximumstrain suddenly as is often unavoidable with vessels at sea, the ropecarries away, due to the fact that manila rope becomes hard and stifi,thus losing most of its elasticity after getting watersoaked. As afurther improvement, to overcome this loss of elasticity in the rope, myrubber core is extended as a cushion between the strands and towards thecircumference of the rope, thus completely cushioning each fibrousstrand and separating them from each other. In this manner, not only isall friction between the strands overcome, but a sudden severe strain ona rope so constucted will i be taken up gradually consequentlypreventing the rop: from parting. Mooring lines used in doc ing vesselsdemonstrate-the need of rope of this cushion construction as theoperation subjects'the' rope to hard uses. The strands under strain willstretch, lengthen out and tend to press themselves into the. cushionwhich due to'its rubber composition is compressed. This compressionslightly reduces the diameter of the rope-allowing the strands tolengthen extensively, thereby increasing the length of the rope. Afterthe rope resumes its original shape. A

As a modification of my rope, I .ma also provide a rubber core in thecenter 0 each strand, and thus increase the pliability of the strands.In the same manner a rubber core may be used in the center of the smallyarns which make up the strands and the rope constructed from such yarnsand strands with my rubber core or with the cushion extending betweeneach strand and towards the cir- 10c cumference of the rope results inan extremely pliable rope. A rope so constructed with the rubber cushionor core, vulcanized to rubber coated fibers, has full protection againstweather or water entirely overcoming all objections with which I amfamiliar. Should the fibers not be rubber coated the cushion or core asthe case may be made to adhere to the strands by coating cores orcushions with adhesive composition previous to laying up in place.

In the accompanyin specification and drawing, I have described andillustrated forms of my invention which have proved highly satisfactoryunder test and in practical use. 7

In the drawing:

Fig. 1 illustrates a cross section of a four strand rope provided withmy core of rubber.

Fig. 2 is a similar view showing each strand provided with a rubbercore.

Fig. 3 is an enlarged similar view, but showing each yarn provided witha rubber heart.

Fig. 4 is an enlarged cross section showing my rubber cushion coreextended to form a complete cushion between each strand and towards thecircumference of the rope.

Fig. 5 is an angular perspective of the same.

Fig. 6 shows a straight ribbed rubber cushlOIl. COIQ.

Figs. 7, 8 and 9 are other cross sections of my rubber cushion core.

My improved rope comprises a plurality of strands of twisted fiber 1laid about a rubber or rubber composition core 2 to which core thefibres may be caused to adhere in any suitable manner. The cores may belaid up with plastic rubber or cement, or the cores may be made soft orsemi-treated. This core prevents the chafing or wearing of the strandsandis extensible to an extent equal to or greater than the extensibilityunder strain of the fibers of the strands 1 which is a markedimprovement over rope constructions heretofore used.

In order further to increase the flexibility and elasticity of thefinished rope, as a modification of my invention I also provide a rubberor other elastic core 3 for each strand of my rope. As a still furthermodfication, each yarn of each strand is in turn provided with a rubbercore 4 which yarns are twisted about the rubber core 3 of each strand 1.(See Fig. 3). I

In Fig. 4 I show my rubber core extended between each strand outwardlytowards the circumference of the rope as ridges or ribs as shown at 5,thus completely cushioning each fiber strand and separating the strandsfrom each other. As above pointed out, such a construction takes care ofany sudden severe strain on the rope and provides an extensibility whichis not present in ordinary fibrous weasel rope. The straight core shownin Fig. 6 may be preferred for use in rope of hard lay as the softrubber will of necessity take up and follow the lay of the strands. Thisis also true in varying degree of the forms of core illustrated in Figs.7, 8 and 9.

By reason of the utilization of rubber cores in turn in the yarns,strands and rope, it is possible to use a cheaper commercial grade offiber which is coarser and of greater tensile strength than is presentin the highest grade rope. On the other hand, by coating the fibres ofthe strands with rubber or other elastic and adhesive material, thefibres are eficctively protected against moisture and are caused toadhere to each other so that it is entirely feasible to form the strandswithout twisting and either with or without central cores. That is tosay, when the fibres are coated they are caused by the coating to adhereto each other, whereby the rope fabrication as an entirety may be ofunitary form, especially since the fibres next to the cores 3 and 4 canbe adhesively united with said cores by the coatings of the fibres ifsaid cores are used. In this connection, it is pointed out that thecentral core 2 of the rope is used regardless of the particularformation of the strands, i. e., whether the strands are or are notprovided with cores and whether they are or are not twisted and made offibres or other suitable non-metallic material. \Vhen the rope materialis coated those strands adjacent to the core 2 may be adhesively unitedtherewith by the coatings. Accordingly, where coated material is usedthe finished rope can be of unitary form with all of the elementsthereof adhesively united with one another. Especially is this so when asingle strand is used as a completed rope in which case a core 3 may belocated centrally of said strand or rope.

It will be understood that my invention contemplates the use of myextensible core in any non-metallic rope construction regardless of theprocess of making the same or the manner of embodying the core therein.Strands of suitable fibrous or other nonmetallic materials may be woundor twisted, if desired, and pluralities thereof again may be twisted toproduce strands or ropes of greater diameter, in each case the centralspace throughout the resulting rope to be occupied in whole or in partby material of an extensibility at least equal to the extensibility ofthe surrounding fabrication.

Each strand as well as the fin shed rope, may be provided with a similarextensible center. If an adhesive material is used to coat the strandsor the parts thereof, the strands may be formed into rope withouttwisting, in which case the finished product is composed of non-metallicmaterial all the spaces of which are filled with a rubber or similarelastic material. The strands may be.made to adhere to each other bysuch elastic material and to the core of the rope, or may adhere to thecore only. Obviously the strands each may be treated without adhering toeach other or to the core.

Various modifications in the manner of cushioning and laying up of myrope as well as in the process of preparing the same may obviously beresorted to without departing from the spirit of my invention if withinthe limits of the appended claims.

What I therefore claim and desire to secure by Letters Patent is:

1. A rope or cable comprsing a plurality of strands of flexible materialand a rubber cushion about which said strands are laid,

each of said strands having a rubber core and a plurality of yarns laidthereabout, and each of said yarns in turn being provided with a rubbercore.

2. A rope or cable comprising a plurality of rope strands and a rubbercushion about which said strands are laid, each of said strands having arubber core of general triangular cross sect on, a plurality of yarns ofrope material laid thereabout, each of said yarns in turn being providedwith a rubber core.

3. A rope or cable comprising a plurality of rope strands and an elasticcushion about which said strands are laid, each of said s'trandshavingan elastic core of general triangular cross section, a plurality ofyarnsof,rope material laid thereabout, each of said yarns inturn beingprovided with an elastic core.

4. A rope composed of fibres commonly twisted together into yarns, saidyarns being 3 twisted together forming strands, and said 40 strandsbeing twisted together to form a continuous fabrication of naturalextensibility, a core axially of said fibrous fabrication and of anextensibility at least equal to the extensibil ty of the surroundingfibre fabrication whereby under tension said core will simultaneouslyfollow in itslextension the stretch of the fibre structure. 1

5. A rope composed of fibres commonly twisted together into yarns, saidyarns'being twisted together forming strands, and said strands beingtwisted together to form a continuous fabrication of naturalextensibility, a core ax ally of said fibrous fabrica tion, said corebeing compressible and hav- EJ ing an extensibility at least equal totheextensibility of the surrounding fibre fab-rice. tion whereby therope is under tension said core is adapted to cushion relative inwardmovement of the strands and to stretch in har- C3 mony with stretchingof the surrounding fibrous fabrication.

I 6. A rope comprising a plurality of fibrous strands each comprisinglong twisted vegetable fibres having individual longitudinal resiliency,and an extensible rubber core having a resilliency at least equal to theresiliency of said strands, whereby upon the longitudinal stretch of theindividual strands there is permitted an equal longitudinal stretch ofthe core.

7. A. rope composed of extensible nonmetallic twisted strands, thecenter of said rope being filled at least in part by an elastic materialhaving an extensibility at least equal to the extensibility of thenon-metallic strands.

8. A rope composed of. extensible nonmetallic twisted strands includingan elastic center element incorporated during the process of fabricatingthe rope, said elastic center element having an extensibility at leastequal to the extensibility of the non-metallic strands. b

9. A rope composed of a core and a surrounding rope fabrication ofextensible fibrous material, the core being elastic and having anextensibility at least equal to the extensibility of the surroundingfibrous fabrication.

10. A rope comprising a core and a surrounding fibrous and extensiblerope fabrication the fibres of which are coated with .an

elastic material and united with each other by said material, the corebeing elasticand having an extensibility at least equal to theextensibility of the surrounding fibrous.

fabrication.

11. A rope comprising a core and ajsurrounding fibrous and extensiblerope fabrication the fibres of which are coated with an elastic materialand united with each other and with'the core by said material, the" corebeing elast c and having an extensibility at least equal to theextensibility of the surrounding fibrous fabrication.

12. A rope as set forth in claim 10 in which the elastic material forthe fibres con sists of rubber.

13. A rope as set' forth in claim 11 inwhich the elastic coatingmaterial for the fibres and the material from which the core" is. formedconsists of rubber.

14. A rope or cable comprising a plurality of twisted strands ofnon-metallic material each of said strands having a core, said corebeing elastic and having an extensibility at least equal to theextensibility of the nonmetallic material, said strands being fabricatedto produce a rope, the center of said --rope being filled in whole or inpart by an elastic material having an extensibility at least equalto,the extensibility of said strands.

In testimony whereof I aflix my signature.

ERNEST V. WYATT.

